Workholding means for blindstitch sewing machines



March 3l. 1925.

C. A. DEARBORN WORKHOLDING MEANS FOR BLINDSTITCH SEWING MACHINES Ao/Mfrs 30 IN1/Enron -Patented `Mar. 31, 1925.

CHARLES A. DEARBOB'N, 0F NEW'- 'YORK, N. Y.

WORXHOLDING MEANS FOR BLINDSTITCH SEWING MACHINES.

Application mea my 1s, 192s. serial No. 639,77?.

T all whom t my concern.'

Be it known that I, CHARLES A. DEARBORN, a citizen of the United States, residing in the borough of Manhattan, city, county, and 5 State of New York, have invented certain Y new and useful Improvements in IVorkhold ing Means for Blindstitch Sewing Machines, of which the following is a specification. The present invention relates particularly tol improvements in the work holding means for loverseaming blind stitch sewing machines of the power driven type, such as illustrated in United States Patent No. 1,- 169,934 granted to me February 1st, 1916.

The machine of said patent was provided with an oscillatory toothed ridge forming rib or disk mounted between yielding cloth supporting plates in position to engage the work beneath the usual slotted presser foot.

'Ihe ridge forming disk of this patented ma:

chine was peculiarly shaped to prevent the objectionable crowding of the work when crossing seams and was formed with one or more clothV engaging teeth to effect the fulling in operation of the disk.

While the machine of said patent has been highly successful in operation upon many classes of work, I have found difficulty with this part of the machine when changing from 0 an operation upon light material having light seams to' heavy material in which the seams are more bulky and particularly where there are crossing seams in the line of stitching. With proper care and adjustment of parts by the operator all classes of work can be satisfactorily performed with the machine of said patent, but the difficulty arises from the carelessness 'or failure of the operator in making the proper adjust- 40 ment when changing from one kind of work to another. f

rI`he present invention consists'of an improved form of ridge forming disk' or rib in a machine of the type referred to. The

new ridge forming disk is made of a relatively thin metal plate having one or more cloth 'engaging teeth and mounted as in the old machine to support a ridge of work in the line of stitching. Associated with this ridge 0` forming disk or plate is a curved cloth supporting finger pivotally `mounted upon ythe disk or plate and held by its controlling spring at a slightly lower level than the active edge of the ridge forming disk, so as to support the heavy seam portions of the piece of work alongside :of the line of stitching.

This spring supported finger is so Iarranged that it will automatically yield upon the ridge `forming disk to permit the free passage of an excess of material, such as when crossing a vseam presented laterally to the line of stitching being formed. Since the spring supported finger yields independently upon the ridge forming disk, it will be clear that the main work support and disk will not be forced away from the plane of action of the needle .so that the stitching operation will not be interfered with. .l

In order that the invention may be fully understood, it will now be described with reference to the accompanying drawings,

and afterwards more particularly pointed out in the annexed claims.

In said drawings: Y Figure l is a side elevation of a blind stitch sewing machine having the present improvement applied thereto.

Figures 2 and 3 are detail sectional viewsillustrating the improved ridge forming disk, the yielding auxiliary supporting finger being shown in extreme positions in' the two views.

Figure 4 is a detail transverse sectional view showing the improved ridge forming disk in position beneath the stationary presser foot of the machine.:

l is the main frame of the blind stitch sewing machine illustrated in my abovel named patent. 3 is the looper bar driven from the main shaft of the machine by a universal joint coupling 2. 5 is the looper adjustably mounted upon the forward end of the looper bar 3. lO is the needle mounted upon the usual rock arm l1 carriedby the needle rock shaft 12. 15 is a stationary presser foot projecting forwardly from the main frame and 20 is the reciprocating feed dogmounted upon the feed lever 21.l

25 is the work support or table hinged to lm').

40 is a ridge forming rib or disk securely,

fastened upon the oscillating shaft 30 between the work supporting plates 35. These parts are so arranged that the work support presents the plates 35 and disk 40 beneath the stationary presser foot l5, the operating edge of the disk 40serving to press a ridge of work up into the slot of ie presser foot in the path of the needle. ,The ridge forming rib or disk 40 is provi`ded with one or more cloth engaging teeth 41 and is cut away in front of said teeth to aEord desirable room for the work in front of the path of the needle. Pivotally mounted-upon one face of the disk 40 is an auxiliary curved work supporting finger .50. This finger 5() is pivoted upon disk 40 by means of a countersunk set screw 51 and is provided with an integral lug 52,

which in its normal raised position' engages the hub of disk 40. A. small spiral spring 53 rests in a shallow recess 4:0a of disk 40 and is connected at one end with the heel 54 of linger 50 and at the other end with the disk 40 for theipurpose of yieldingly holding the ringer in its normal position as shown in F igurcl 2. This finger 50 is formed with a tooth 55 and a reduced forward end to afford ample room for the work adjacent to the path ofthe needle.

In operating a machine with the improved ridge forming rib or disk, it lwill be understood that by the usual adjustmentof the work support and the tension of its spring, the action of the rib with respect to the stitching operation is determined to suit the particular work. The position of the disk 40 is--automatically determined by the thickness-of goods passing over the rib beneath the presser foot. In case a piece of work presents an unusual cross-seam or bulky part of material to the right'ofthe ridge forming' disk, it will pass over the auxiliary finger 50 and cause the finger to yield upon the disk 40 without altering the relation ol disk 40 to pass beneath so that the accuracy of the stitching operation is not interfered with. The tooth 55 of auxiliary linger 50 coperates with the cloth engaging teeth 41 of disk Ll0 in their fulling-i7 or auxiliary feeding action upon the under surface of the work. In the machines with the old formv of ridge forming rib, such as shown in my above named patent, the passage of an eXtra thickness of material to the right of the line of stitching causes exceptional thumping or vibrating action and at times prevents perfect sewing over the heavy seams. With the improved ridge forming rib this objectionable action is entirely avoided and. it will befound that the machine moves as uniformly and evenly over heavy' seams as it does upon the general run of work.

l claim: l

1. In a sewing machine, the combination with a work support, a presser foot, and stitch forming mechanism, of a ridge forming rib carried by said'work support and an auxiliary cloth supporting member yieldingly mounted upon said ridge forming rib.

2. In a sewing machine, the combination with a work support, a presser foot, and stitch forming mechanism, of a ridge forming rib carried by said work support, and an auxiliary cloth supporting member pivotally mounted upon said ridge forming rib.

3. In a Sewing machine, the combination with a work support, a presser foot, and

stitch .forming mechanlsm, of a curved ridge forming rib carried by said work support, and a curved auxiliary cloth supporting member yieldingly mounted upon said ridge forilping rib and normally concentric therewit 4. In a sewing machine, the combination with a machine frame, a slotted presser foot carried by said frame, suitable stitch forming mechanism, and a work support mounted upon said frame, of an oscillating ridge forming rib carried by said work support beneath said presser foot, and a spring actuated cloth supporting arm pivotally mounted upon said ridge forming rib.

5. In a sewing machine, the combination with a machine frame, a slotted presser foot carried by said frame, suitable stitch forming mechanism, and a work support mounting mechanism, a work support mountedL upon said frame, and two cloth supporting plates yieldingly mounted upon said work support beneath said presser foot, of an oscillating ridge forming rib carried by said work support between said plates, and a spring actuated cloth supporting arm pivotally mounted upon said ridge forming rib.

7. In4 a sewing machine, the combination with a work support, a presser foot, and stitch forming mechanism, of a curved ridgel forming rib `carried by said work support having a relatively low peripheral portion in front of and below the path of the needle to afford space for the work, and an auxiliary cloth supporting arm yieldingly mount ed upon said ridge forming rib and normallyl concentric with the high portion of the p periphery thereof.

8. In a sewing machine, the combination with Aa, work support, a presser foot, and stitch forming mechanism, of atoothed ridge stitch forming mechanism, of a toothed forming. rib carried by said supportl and 10 ridge forming rib carried by s'aid work suphaving a relatively low peripheral portion port, and a toothed auxiliary clothpsupportin front of and below the path of the needle,

. 5 ing arm yieldingly mounted upon said ridge and a toothed auxilia cloth supporting v 'forming rib. f arm yieldingly mou te upon said ridge 9. In a sewing machine, the combination forming rib. 1 with a work support, a presser foot, and CHARLES A. DEA`RBORN. 

